Disc brakes for automobiles and other wheeled vehicles are well known in the art. A disc brake system generally comprises a rotor rigidly attached to the wheel and a caliper which is actuated to close upon the surface of the rotor to retard its rotational movement, thereby causing braking of the wheel. When the caliper is released, the brake rotor can spin freely permitting normal rotation of the wheel.
Brake pads attached to the caliper are designed to wear during braking and require periodic replacement. Replacement of the brake pads is effected by removing the caliper assembly from the disc brake.
Typically, the caliper assembly is mounted by a pair of specially configured mounting bolts to a cast-iron steering knuckle or other support structure. The bolts along with associated bolt sleeves serve as retaining pins for the caliper assembly. In its mounted position, the caliper assembly floats on the pin surfaces to accommodate normal wear of the brake pads. In many models, the bolts are threadingly engaged with a steering knuckle or similar support structure in order to retain the bolts in place.
To remove the caliper assembly, the two caliper mounting bolts are removed. However, in many instances, during servicing of the disc brakes, the threads within one of the apertures defined in the steering knuckle become stripped. One of the contributing factors to this problem is that the bolts are usually steel which is a harder substance than the steering knuckle which is usually cast-iron.
Prior to this invention, one of two solutions were generally used to remedy this thread stripping problem. The first solution was replacement of the entire steering knuckle. Such replacement is a very time consuming and expensive solution to the problem.
The second solution was to repair the threads using an insert to define a new thread within the cast-iron housing. Such method requires the enlargement of the stripped aperture within the housing and the installation of the threaded insert therein, the insert having a threaded aperture of the required size. This procedure is detailed in Undercar Digest, September, 1991, pp. 26-28, which article is incorporated by reference herein as if fully set forth.
While this latter solution is much less time consuming and much less expensive than replacing the entire steering knuckle, it is still a relatively time consuming operation.
It would be desirable to simplify the repair of this problem associated with servicing disc brakes.